Method of producing α2,3-sialyltransferase

ABSTRACT

A method of preparation of lysate having α2,3-sialyltransferase activity is disclosed. A cell culture having essentially no endogenous expression of eukaryotic α2,3-sialyltransferase is infected with myxoma virus. The harvested triton lysates include significant quantities of a protein having eukaryotic α2,3-sialyltransferase activity. Compositions having in vitro α2,3-sialyltransferase activity and comprising a protein extract of lysates of the aforementioned lysates are also provided for.

This invention relates to a method of producing α2,3 sialyltransferase.

This invention has particular but not exclusive application to production of an enzyme having eukaryotic α2,3-Galβ1,3(4) GlcNAc sialyltransferase activity, and for illustrative purposes reference will be made to such application. However, it is to be understood that this invention could be used in other applications, such as production of assays for enzymes having eukaryotic α2,3-Galβ1,3(4) GlcNAc sialyltransferase activity.

The glycosyltranferases are a highly polymorphic group of membrane-bound enzymes of endoplasmic reticulum and Golgi bodies that catalyze the transfer of a single monosaccharide unit from a nucleotide donor to the hydroxyl group of an acceptor saccharide in the biosynthesis of N-glycan (Asn-GlcNAc N-glycosidic linkage; GlcNAc, N-acetylglucosamine) and O-glycan (Ser/Thr-GalNAc, O-glycosidic linkage; GalNAc, N-acetylgalactosamine) moieties of glycoproteins and glycolipids.

The eukaryotic sialyltransferases comprise a family of glycosyltransferases that catalyze the transfer of N-acetylneuraminic acid (NeuAc), a sialic acid (SA), from CMP-SA to oligosaccharide chains of glycoconjugates. The addition of the SA normally terminates oligosaccharide chain elongation except for polysialic chains found on neural cell adhesion molecule and gangliosides.

Known eukaryotic sialyltransferases involved in the synthesis of N- and O-glycan derivatives of glycoprotein and glycolipid are summarized in Table 1, adapted from Palcic (1994 Methods in Enzymology, 230:300). In the table, the transferred sugar residue is in bold, and R represents the remainder of the acceptor glycoprotein, glycolipid or oligosaccharide chain.

                  TABLE 1                                                          ______________________________________                                         Sialyltransferase (ST)                                                                     EC number Linkage synthesised                                      ______________________________________                                         Gal(2-6)-ST(ST6N)                                                                          2.4.99.1  NeuAcα2->6Galβ1->4GlcNAc-R                      GalNAcα(2-6)-ST 2.4.99.4 NeuAcα2->6GalNAcα-R                 (ST6OI)                                                                        Gal(2-3)-ST(ST3O) 2.4.99.4 NeuAcα2->3Galβ1->4GalNAcα-R        Gal(2-3)-ST(ST3N) 2.4.99.6 NeuAcα2->3Galβ1->3/4GlcNAc-R           ______________________________________                                    

GalNAcα(2-6)-ST(ST60II)2.4.99.7 NeuAcα2→3Galβ1→3GalNAc-R N-Ac-neuramide α(2-8)-2.4.99.8 NeuAcα2→8NeuAcα2→Galβ-R sialyltransferase

Proteins produced by prokaryotes rarely possess N-terminal sugar chains, whereas eukaryotes exhibit many examples of such glycoproteins. α2,3-sialyltransferases are useful eukaryotic enzymes for in vitro synthesis of N-linked and O-linked sialyl derivatives of glycoproteins, for determinations of acceptors, and other qualitative and quantitative research of glycoproteins.

Only three glycosyltransferases are commercially available. These are the β1,4-galactosyltransferase (EC 2.4.1.38/2.4.1.90) isolated from bovine and human milk, the α2,6 Galβ1,4 GlcNAc-sialyltransferase (ST6N, EC 2.4.99.1) isolated from rat liver, and the α2,3 Galβ1,3 GalNAc-sialyltrasferase (ST30, EC 2.4.99.4) isolated from porcine liver. The ST30 enzyme has been withdrawn from the market by its erstwhile suppliers. No commercial source of α2,3 Galβ1,3(4) GalNAc-sialyltrasferase (ST3N) or other glycosyltransferases currently exist.

No high expression vectors for cloned transferases are widely available, and accordingly most researchers isolate the required glycosyltransferases from mammalian tissues. Isolations from mammalian tissues are complicated by the low natural abundance of the glycosyltransferases and the need for chromatography for partial purification. These factors combine to render the isolates prone to contamination with other glycosyltransferases as well as enzyme inhibitors, resulting in poor and inconsistent results.

A method for partial purification of ST3N from rat liver is described by Palicic (1994, Methods in Enzymology 230:300) following the procedure of Weistein et al (1982, J.Biol.Chem. 257:13835). However, this process requires the use of animals as the source of the tissues and therefore adds to the number of animals sacrificed. Ethical considerations oblige researchers to seek and use procedures and processes that do not require animals where that is possible.

In another approach to production of enzymes having α2,3-sialyltransferase activity, U.S. Pat. No. 5,384,249 (Sasaki, et al.) discloses a method comprising isolation of cDNA coding for enzyme having the activity of an α2,3-sialyltransferase from a cDNA library constructed from mRNA of human cell lines TYH (human histiocytic leukemia cell line) or WM266 (human melanoma cell line), insertion into an expression cloning vector and selection against a lectin medium. The selected clones are isolated, amplified and target DNA isolated from the vector. After coupling to a suitable promoter, the cDNA isolate is used to transform a suitable prokaryote or eukaryote host cell for expression.

The process of the disclosed method is of course a complex one and in keeping with many like processes the efficiency of expression of the inserted exogeneous DNA may vary over time. Further, inhibition may preclude commercially useful expression of the enzyme exhibiting α2,3-sialyltransferase activity.

The present invention aims to substantially alleviate at least one of the above disadvantages and to provide a method for the preparation of α2,3-sialyltransferase which will be reliable and efficient in use. Other objects and advantages of this invention will hereinafter become apparent.

With the foregoing and other objects in view, this invention in one aspect resides broadly in a method of preparation of lysates having α2,3-sialyltransferase activity including the steps of:

infecting a cell culture having essentially no endogenous expression of eukaryotic α2,3-sialyltransferase with a poxviral agent including a gene expressing on infection a protein having eukaryotic α2,3-sialyltransferase activity, and a promoter therefor, and

harvesting a lysate of said infected cell culture containing a protein having α2,3-sialyltransferase activity.

In a further aspect this invention resides broadly in compositions having in vitro α2,3-sialyltransferase activity and comprising a protein extract of lysates of a eukaryote cell culture, having essentially no endogenous expression of eukaryotic α2,3-sialyltransferase, cultured with a poxviral agent including a gene and promoter expressing in said culture a protein having eukaryotic α2,3-sialyltransferase activity.

The applicant has unexpectedly determined that certain poxviral genomes include genes coding for proteins having eukaryotic α2,3-sialyltransferase activity, which are expressed in infected substrates to a commercially useful degree. Especially, it has been determined by the applicant that Leporipoxvirus including the Brazilian myxoma virus (MYXV), Shope (rabbit) fibroma virus, hare fibroma virus, squirrel fibroma virus and Californian myxoma virus. MYXV naturally infects the Brazilian tapeti (Sylvilagus brasiliensis) and causes the development of a small localised tumour which persists for several months and then regresses rapidly. In contrast to the trivial symptoms in its natural host, infection of the European rabbit (Oryctolagus cuniculus) with MYXV causes the devastating disease myxomatosis.

Preferably the poxvirus is selected from the myxoma viruses of rabbits including a wild type endogenous gene and promoter coding for a eukaryotic α2,3-sialyltransferase. However, it is envisaged that sialyltransferase gene encoded by myxoma virus may not be unique to this virus and could be encoded by other poxviruses of the Leporipoxvirus genus.

Related sialyltransferase genes could also be encoded by other genera of the sub-families Chordopoxvirinae, Entomopoxvirinae and unclassified viruses of the family Poxviridae (Esposito 1991, Archives of Virology (Suppl) 2:91). Examples of potential candidate poxviruses are given in Table 2.

                  TABLE 2                                                          ______________________________________                                         Family: Poxviridae; Subfamily: Chordopoxviridae                                     Genus           Prototype virus                                           ______________________________________                                         Orthopoxvirus    vaccinia virus                                                  Parapoxvirus orf virus                                                         Capripoxvirus sheep pox virus                                                  Suipoxvirus swinepox virus                                                     Leporipoxvirus myxoma virus                                                    Avipoxvirus fowlpox virus                                                      Yatapoxvirus yaba monkey tumour virus                                          Molluscipoxvirus molluscum contagiosum virus                                 ______________________________________                                    

Sialyltransferase assays of poxvirus infected cell lysates, as described in this application, may be used to determine if the individual poxvirus species express an active sialyltransferase enzyme. These assays may be conducted by observing the transfer of a labelled sialic acid from CMP-SA to a glycoconjugate acceptor. Such labelled donors may be CMP-[H³ ]SA, CMP-[C¹⁴ ]SA or CMP-9 fluoresceinyl-SA (Gross et al, 1990, Analytical Biochem, 186:127). The labelled acceptors may be visualised by SDS-PAGE or thin layer chromatography followed by autoradiography or fluorography. Alternatively when using CMP-9-fluoresceinyl-SA the labelled acceptor may be separated by from donor molecules by Sephadex G-50 fine chromatography and the extent of labelling of the acceptor measured using a florescence spectrophotometer (fluorometer).

Other poxviruses may contain a related sialyltransferase gene located in the same genomic location as the myxoma virus Uriarra and Lausanne strains, ie between the genes equivalent to A51 and A52 of the Copenhagen strain of vaccinia virus (Goebel et al, 1990, Virology 179:247). These related sialyltransferase genes could be isolated by polymerase chain reaction using appropriate primers.

Accordingly, in a further aspect, this invention resides in the set of degenerate primers: [SEQ ID NOS:192]

CAP-I

GGGATCCAT[A/T/C]TC[T/C]AG[A/G]CA[T/C]AA[A/G]CG

CAP-11 GGGATCCGC[A/G]CA[T/C]AA[A/T/C/G]CC[T/G/A]ATCAT

These primers have been designed based on conserved amino acids between the variola and myxoma viruses. CAP-I is located within the A51 gene corresponding to the translation I-S-R-H-K-R. CAP-II is complementary to the A52 gene sequence corresponding to the translation M-I-G-L-C-A. Amplification of poxvirus DNA using these primers should generate a product of 0.9 kb for viruses which do not encode additional DNA between A51 and A52 (no sialyltransferase gene at this genomic location), and 1.9 kb or larger for viruses which contain addition DNA sequence between the A51 and A52 genes. For the myxoma viruses, 1.9 kb, the addition of 1 kb of DNA corresponds to the sialyltransferase gene.

Vaccinia virus contains a conservative substitution within primer site CAP-I with Q codon instead the K codon of variola and myxoma viruses. This results in a mismatch at position 20 to the oligonucleotide CAP-I. Nevertheless under the amplification conditions a major 0.9 kb product was generated using a vaccinia virus, strain wr, DNA template. Indicating that the primers can tolerate minor mismatch during the amplification procedure.

Myxoma virus is known to replicated in a number of permissive cultured cells of rabbit, chicken, squirrel, hamster, monkey and guinea pig (McFadden, 1988, In "Virus diseases in laboratory and captive animals." Ed. G Darai. Martinus Nijhoff Publishing, Boston. pp36-62). This laboratory has successfully cultured myxoma virus on RK13 (ATCC CLL-37), SIRC (ATCC CLL-60), CV1 (ATCC CLL-70) and VERO (ATCC CLL-81) cells. Attempts to generate productive infection of Human 143B (ATCC CRL-8303), L-M (TK-) (ATCC CLL-1.3) or BHK-21 tk-ts13 (ATCC CRL-1632) were unsuccessful indicating they are non-permissive for viral replication.

Studies have shown that infection of non-permissive culture cells with poxvirus can result in a block to virus DNA replication and thus late gene transcription and viral morphogenesis. Under these circumstances there is no switch from early to intermediate/late gene transcription therefore early genes continue to be transcribed and expressed resulting in an amplification of viral early proteins.

Accordingly, in a further aspect this invention resides in a method for producing myxoma virus sialyltransferase comprising harvesting viral early proteins amplified in a cell line non-permissive for viral replication, and isolating said myxoma virus sialyltransferase.

The myxoma virus sialyltransferase gene is transcribed during the early phase of infection, therefore infection of one of the above described non-permissive cell lines may result in an amplified sialyltransferase activity in the triton cell lysates compared to permissive cell viral infection.

Accordingly, cell cultures may be selected from those permissive for infection by myxoma, such as rabbit cells per se having essentially no endogenous expression of eukaryotic α2,3-sialyltransferase. However, it is envisaged that circumstances may provide for the use of other cell cultures such as the African green monkey cell line CV1 (ATCC CCL70), permissive for the virus and further permissive as a negative control with Vaccinia virus. Additionally, it is envisaged that certain non permissive cell lines may be useful where the early-expression sialyltransferase product is produced on infection prior to inhibition of the virus.

As used herein, the expression "having essentially no endogenous expression of eukaryotic α2,3-sialyltransferase" should be taken to means that the enzyme if produced endogenously in the selected cells occurs in such minute quantities that expression of the product enzyme of the invention effectively masks all detection. Additionally, it is preferred that the cells are selected for essentially no endogenous expression of other sialyltransferases.

It has been surprisingly determined that commercially useful titres of a polypeptide having α2,3-sialyltransferase activity are obtained in lysates of in vitro infection and culture of cells, having little or no endogenous sialyltransferase expression, with myxoma virus. This unexpected result appears not to be subject to cellular inhibition, and the lysates are statistically substantially pure with respect to the target α2,3-sialyltransferase as opposed to competing enzymes of differing specificity such as cellularly mediated 2,6 sialyltransferases. Conventional wisdom would have it that the cultured cells should be those having endogenous expression of the enzyme, such as liver cells.

In order that this invention may be more readily understood and put into practical effect, reference will now be made to the accompanying examples and sequence listings which illustrate a preferred embodiment of the invention, described with reference to FIGS. 1 to 5, wherein:

FIG. 1 comprises the EcoRI restriction map of the myxoma virus genome, illustrating above the map the location of the sialyltranferase gene (MST3N);

FIG. 2 is a fluorograph showing ³ H-labelled sialylated fetuin following sialyltransferase and PNGaseF reactions, wherein the lysates correspond to lanes: 1) Vaccinia virus; 2) as 1+PNGaseF; 3) vaccinia virus+5 mUnits ST6N; 4) as 3+PNGaseF; 5) myxoma virus; 6) as 5+PNGaseF; 7) Lu (MST3N⁻ /lacZ⁺); 8) as 7+PNGaseF.

FIG. 3 comprises lectin binding assays wherein: Lanes 1 & 6. MYXV+CMP-SA; Lanes 2 & 7 MYXV; Lanes 3 & 8 VACV+CMP-SA+ST6N; lane 4 & 9 VACV+CMP-SA; lane 5 & 10 VACV. A) lectin SNA-DIG & B) lectin MAA-DIG;

FIG. 4 shows lectin binding assay using MAA-DIG to extracts of poxvirus infected RK13 cells, wherein lanes are: 1) VACV+ST6N; 2) VACV; 3) SFV; 4) MSD; 5) MSW; 6)

Lu, and

FIG. 5 comprises the Northern blot of myxoma virus Lu RNA.

Sequence 1 [SEQ ID NO:3] comprises Myxoma virus MA51 [SEQ ID NO:4] and protein kinase (MB1) [SEQ ID NO:8] genes, partial cds, alpha-2,3-sialyltransferase (MST3N) [SEQ ID NO:9], (MA52) [SEQ ID NO:5, (MA55) [SEQ ID NO:6] and (MA56) [SEQ ID NO:7] genes, and Sequence 2 [SEQ ID NO:10] comprises Myxoma virus (MA51) [SEQ ID NO:11] and (MA52) [SEQ ID NO:12] genes, partial cds, alpha-2,3-sialyltransferase (MST3N) [SEQ ID NO:13] gene, complete cds.

EXAMPLE 1

Myxoma virus genomic restriction mapping and sub-cloning studies were conducted by Russell and published in Russell & Robbins (1989) Virology 170:147. The myxoma virus DNA contained within the clones was not characterised at either the nucleotide or genetic level, but have been a major source of myxoma virus material for the development of the present invention. The myxoma virus DNA clone used in this invention was derived from a laboratory derivative of the Uriarra strain, (Mykytowycz, (1953) Nature 172:448; Russell & Robbins, 1989) which is an Australian field derivative of the Standard Laboratory Strain (SLS, ATCC VR-116), itself derived from the Moses strain, which was released in Australia in 1950.

The myxoma virus, strain Uriarra, EcoRI-G2 fragment was obtained from pUrE-G2 (Russel & Robbins, 1989) and subcloned into pGem7Z(f-) (Promega Corporation). The SalI-R2 fragment contained within the EcoRI-G2 DNA fragment was subcloned into pGem3Z(f+) (Promege Corporation) and a partial DNA sequence determined. The DNA sequence determined contained a "unique" poxvirus gene/protein which when used to scan the GENBANK database using the BLASTp program with default parameters contained similarity to the human "CD75 antigen". The human gene was later found to actually encode an α2,6-sialyltransferase (ST6N) which is responsible for formation of the sialic acid-containing CD75 antigen. (Stamenkovic et al.,1990, J.Exp.Med. 172:641; Bast et al.,1992, J.Cell.Biol. 116:423)

The DNA sequence of the larger region of the EcoRI-G2 myxoma virus fragment which corresponds to the BamHI-N fragment plus the DNA sequence to the right-hand end of the EcoRI-G2 fragment was determined. The myxoma virus genes encoded by this region are MA51 (partial sequence), MA51a (MST; α2,3-sialyltransferase), MA52, MA55, MA56 (orthopoxvirus haemagglutinin related) and MB1 (serine/threonine kinase related). Five of these genes show nucleotide similarity to vaccinia virus, strain Copenhagen, genes A51 through B1 (Goebal et al, 1990 Virology 179:247), the sixth gene, MST3N, being a newly identified poxvirus gene showing similarity to eukaryotic sialyltransferases.

Transcription analysis of the wild type Lausanne strain (Lu;ATCC VR-115: Bouvier, 1954, Bulletin de l'Office International des Epizooites 46:76) MST3N gene was conducted essentially as described in Jackson & Bults, (1992, J Gen. Virol. 73:3241). Both myxoma virus early and late polyadenylated mRNA preparations were hybridized to a P³² -labelled strand specific RNA probe for the MST gene. The autoradiograph was developed and demonstrated that the MST gene is transcribed early in infection giving a major transcript of approximately 1100 nucleotides. It appears that either the major MST early MRNA persists late in infection or transcription of the early promoter is re-initiated during late infection as significant levels of MST early sized transcripts were still present during late phase of infection.

A recombinant myxoma virus, Lu(MST-,LacZ⁺), was constructed using wild-type Lausanne strain, with the MST gene disrupted by insertion of the E.coli lacZ gene into the region encoding the sialyl motif. This recombinant virus was constructed to demonstrate that the MST3N gene encoded a protein responsible for the sialyltransferase activity observed in cell lysates of wild-type virus.

Triton detergent lysates of tissue culture cells infected with either vaccinia virus (strain wr;ATCC VR-119), myxoma virus (strain Lu) or Lu (MST-,lacZ⁺), were prepared and used in in vitro sialyltransferase reactions. These experiments demonstrated that the myxoma virus infected cells contained an easily detectable sialyltransferase active which transferred [H³ ]--labelled sialic acid to the asialylated acceptor glycoprotein as determined by SDS-PAGE and fluorography using an overnight exposure. Vaccinia virus infected cells treated in an identical manner do not show detectable sialyltransferase activity. The myxoma virus sialyltransferase activity was abolished when the MST gene is disrupted, Lu (MST-,lacZ⁺), demonstrating that the identified MST gene encodes a protein with sialyltransferase activity. These experiments also demonstrated that endogenous cellular sialyltransferase activity was below detection limits on overnight exposure of the fluorographs although very weak signals could be detected on extended exposure (4 days). The experiments with the MST-recombinant myxoma virus also demonstrates that infection with myxoma virus does not induce increased cellular sialyltransferase activity.

The nature of the myxoma virus sialyltransferase directed oligosaccharide linkage (O or N linked) to the glycoprotein acceptor was determined by treatment of the myxoma virus sialyltransferase [H3]-SA labelled glycoprotein acceptor with PNGase-F, which removes N-linked oligosaccharide from protein substrates. Using this glycosidase all the [H³ ]-labelled sialic acid was N-linked but not O-linked, as illustrated in FIG. 2, wherein lane 1 and 2 are vaccinia virus strain wr cell lysate, lanes 3 and 4 are vaccinia virus wr infected cell lysate plus 5 mUnits of α2,6-sialyltransferase(ST6N), lanes 5 and 6 are myxoma virus Lu infected cell lysate, and lanes 7 and 8 are recombinant myxoma virus Lu(MST-,lacZ⁺) infected cell lysate. Lanes 2, 4, 6 and 8 also included 0.4 units of N-glycosidase-F.

The nature of the type of sialic acid linkage (α2,3 or α2,6) was determined by saturation labelling of asialylated glycoprotein acceptor with "cold" sialic acid using the myxoma virus cell extract and determining the type of linkage using digoxigenin labelled lectin binding assay, as per FIG. 3, wherein:

Lanes 1 and 6: myxoma virus Lu infected cell lysate plus CMP-SA

Lanes 2 and 7: myxoma virus Lu infected cell lysate without CMP-SA

Lanes 3 and 8: vaccinia virus wr strain infected cell lysate plus 5 mUnits of α2,6-sialyltransferase (ST6N) plus CMP-SA

Lanes 4 and 9: vaccinia virus wr strain infected cell lysate plus CMP-SA

Lanes 5 and 10: vaccinia virus wr strain infected cell lysate without CMP-SA.

Lanes 1 to 5 were treated with the lectin probe Sambucus nigra agglutinin (SNA), specific for α2,6 linked SA, while lanes 6 to 10 were probed with Maackia amurensis agglutinin (MAA) specific for α2,3 linked SA. This demonstrated that the myxoma virus sialyltransferase specifically generates an α2,3 linkage to the glycoprotein acceptor.

The above results taken with the amino acid similarity to known sialyltransferases indicates that the MST3N gene encodes an active α2,3 Galβ1,3(4) GlcNAc-R sialyltransferase with a specificity for N-linked glycoprotein (ST3N; EC:2.4.99.6).

A) Identification of Myxoma Virus Sialyltransferase Gene DNA Sequencing and Plasmid Construction

The myxoma virus 7.3 kb EcoRI-G2 DNA fragment located approximately 130 Kb from the left end of viral genome (FIG. 1) was sub-cloned in both orientations into pGem7Z(f-). A 4.7 kb of the DNA sequence was determined which corresponds to the right-end of the EcoRI-G2 fragment (see sequence listings).

The DNA sequence contains six open reading frames, five ORFs correspond to gene homologues (A51, A52, A55, A56 & B1) found in vaccinia virus (an Orthopoxvirus) and the sixth ORF, MST3N, shares similarity to known sialyltransferases (table 3).

The MYXV SalI-R2 fragment was ligated into the SalI site of pGem3Z(f+), generating pUrS-R2. The MYXV DNA fragment contained in pUrS-R2 was removed by digestion with EcoRI and HindIII and ligated between the respective sites of the transient dominant selection vector pGP7.5 gpt, generating pUrST1. The MST3N gene sequences contained in pUrST1 were interrupted by the insertion into the unique BglII site, a cassette.

B) Characterisation of the Sialyltransferase Activity Cells

SIRC (European rabbit (Oryctolagus cuniculus) cornea, ATCC CCL-60), RK13 (O. cuniculus kidney, ATCC CCL-37) and CV-1 (African Green Monkey (Ceropithecus aethiops) kidney, ATCC CCL-70) were maintained in Minimal Essential Medium (MEM) supplemented with 5% (v/v) foetal bovine serum (FBS).

Viruses

a) Brazilian MYXV strains, Lausanne (Lu) (ATCC VR-115) isolated Campinas, Brazil, 1949 and Uriarra (Ur) isolated Australian Capital Territory, 1953 and is therefore a derivative of the Moses strain (ATCC VR-116) isolated Sao Paulo, Brazil 1909.

b) Vaccinia virus (VACV) strain wr (ATCC VR-1354).

c) Recombinant myxoma virus Lu (MST3N⁻ /lacZ⁺) was constructed by liposome mediated transfection of Lu infected SIRC cells with pUrST1-lacZ and isolated using the transient dominant selection procedure as described previously.

Triton Cell Lysate Preparation

Confluent monolayers of CV1 cells were infected with poxvirus at an M.O.I of 1, in 80 cm² culture flasks. Twenty-four hours post-infection the cells were detached with PBS-EDTA at 37° C. and washed three times using PBS at 4° C. Cell lysates were prepared by suspension in 1 ml per flask of 50 mM MES-OH, pH 6.1; 0.5% (v/v) Triton-X100; 100 mM NaCl; 1.5 mM MgCl₂ ; 0.1 mM PMSF; 10 μg/ml aprotinin and incubation at 4° C. for 45 minutes. The lysate was clarified by centrifugation at 1750 g at 4° C. for 15 minutes. Supernatants were stored at -70° C. Total protein concentrations were measured using the BCA Protein Assay Reagent (Pierce).

Sialyltransferase Reactions

Cell lysates, 30 μl (containing 50 μg total protein), were mixed with 5 μl of asialofetuin (Sigma Type-I; 10 mg/ml in MES buffer [50 mM MES-OH, pH6.1; 0.5% (v/v) Triton X-100]) and 5 μl CMP-[³ H]-SA (DuPont NEN; dried and dissolved in MES buffer at 1 μCi/μl) and incubated for 90 minutes at 37° C. Reactions were terminated by heating at 90° C. for 10 minutes. An assay containing a vaccinia virus infected cell lysate sample was used as a negative control. A positive control consisted of the vaccinia virus infected cell lysate including 5 mUnits of α2,6-sialyltransferase (ST6N;EC:2.4.99.1; Boehringer-Mannheim).

PNGase-F Digestion

The total protein from the sialyltransferase reactions were precipitated using 8 volumes of acetone at -20° C. overnight and recovered by centrifugation for 30 minutes using a microcentrifuge. Protein pellets were air dried and resuspended in 10 μl of H₂ O. The samples were denatured by the addition of 25 μl 0.1 M 2-Mercaptoethanol/0.5% (w/v) SDS and heated at 100° C. for 5 minutes. Samples were cooled to room temperature and the total volume adjusted to 40 μl with H₂ O. Denatured protein aliquotes of 5 μl were mixed with 5 μl PNGase-F buffer (2X) [40 mM sodium phosphate buffer, pH 7.2; 20 mM EDTA; 3% (w/v) CHAPS]. Reactions were initiated by the addition of 0.4 Units N-Glycosidase F (Boehringer-Mannheim) and incubated at 30° C. for 16 hours. The reactions were terminated by heating at 100° C. for 5 minutes.

Polyacrylamide Gel Electrophoresis and Fluorography

Samples containing approximately 6 μg of the acceptor glycoprotein were separated by SDS-PAGE, fixed and stained within the gel. Flurographic detection of the labelled sialoglycoproteins (FIG. 2) was achieved by impregnating the stained gels with Amplify (Amersham) drying at 80° C. and exposure for 24 to 48 hours to pre-flashed Hyperfilm-MP (Amersham).

Determination of Sialoglycoprotein by Lectin Binding

For total "cold" sialylation of acceptor glycoprotein, triton lysates of viral infected cells (30 μl) were mixed with 5 μl of asialofetuin (10 mg/ml) with/without 10 μl of CMP-SA (10 mM; Sigma) and incubated at 37° C. for 24 hours. Glycoprotein samples (12 μg acceptor glycoprotein) were separated by SDS-PAGE and electrophoretically transferred to PVDF membrane. Determination of the bound SA linkage to glycoprotein acceptor was accomplished using the DIG Glycan Differentiation Kit (Boehringer-Mannheim), using DIG labelled lectins, Sambucus nigra agglutinin (SNA; for 2,6 linked SA) and Maackia amurensis agglutinin (MAA; for 2,3 linked SA) as recommended by the manufacturer (FIG. 3).

Sialyltransferase activity of other leporipoxviruses (Californian myxoma viruses MSW San Francisco; MSD San Diago; SFV-OA Shope Fibroma virus Origional A strain) were analysed using the lectin binding assay as described above. All viruses express a similar sialyltransferase activity to Brazilian myxoma virus (FIG. 4), indicating that expression of an active "2,3 sialyltransferase is representative of the genus.

c) Determination of Time of Maximal Sialyltransferase Expression

Confluent (25 cm²) RK13 cells were infected at an multiplicity of infection (MOI) of 5 with MYXV strain Lu and incubated at 33° C. At 10, 17 24 and 48 hours post infection, triton cell extracts (300 μl) were prepared as described above. Sialyltransferase activity (using fluorescence assay below) appears to be maximal between 24 and 48 hours post infection and coincides with maximal cytopathic effect (data not shown).

Sialyltransferase assays were performed using CMP-9-fluoresceinyl-SA (Boehringer Mannheim) as donor in 20 μl buffer (50 mM MES pH6.1; 0.1% Triton X-100 containing CMP-9-fluresceinyl-SA, 20 μM; acceptor glycoproten asialofetuin (Sigma) 1.5 mg/ml) at 37° C. for 15 minutes. Reaction were terminated by the addition of 4 μl of 0.1 M CTP. Labelled acceptor glycoprotein was separated from unincorporated donor by Sepadex G-50 gel filtration (NICK Spin columns; Pharmacia) using 0.1 M Tris pH8.6 as elution buffer. The extent of labelling of glycoprotein was determined using a CytoFluor II Fluorescence Reader (PerSeptive Biosystems) and 96 well plates.

d) Estimation of Sialyltransferase Activity

Ten 180 cm² flasks of confluent RK13 cells were infected at a MOI of 5 with Lu and harvested at 24 hrs PI when 100% CPE was evident. A triton cell extract (total 20 ml containing 3.1 mg total protein/ml isolated from 1.83 g of wet cells) were prepared as described above and used for a fluorescence sialyltransferase assay. A commercially available sialyltransferase (α2,6-sialyltransferase EC:2.4.99.1 Boehringer Mannheim 83361420-Jul. 31, 1997) was used as a control to determine relative sialyltransferase activity.

Relative Sialyltransferase Activities:

Samples (10 μl) were used in reactions standardised to include 25 μg of total protein (RK13 cell lysate) in a 25 μl volume.

Raw Data [CytoFluor II Fluorescence Reader (PerSeptive Biosystems)]

Excitation 485: Emission 530: Gain 51

Data analysed and concentrations determined using Microplate

Manager II (V3.0) (BioRad)

Sample: Cytofluor reading

Blanks: 74 average

ST6N standards: 8 U/mg enzyme activity at 37° C. with CMP-N-acteylneuramic acid as substrate (approx. 2.5 U/mg enzyme at 37° C. with CMP-9(3-fluresceinyl-thioureido)-9-deoxy-N-acteyl-neuraminic acid as donor): units below are predicted activities of diluted enzyme relative towards CMP-SA.

100 μunits: 1231/1140

50 μUnits: 583/537

25 μUnits: 309/283

Unknowns

Uninfected RK13 cells 10 μl neat sample (25 μg protein):

99/86=0.9 μUnits sialyltransferase

MYXV infected RK13 cells 10 μl of 1:10 dilution (3.17 μg protein) no glycoprotein acceptor: 111/103(activity to wards endogenous acceptors in RK13 lysate).

MYXV infected RK13 cells 10 μl samples

1:10 dilution (3.17 μg protein): 1332/1141=105.7 μUnits sialyltransferase

1:20 dilution (1.59 μg protein): 777/749=65.4 μunits sialyltransferase

Relative Specific Activities

RK13 cells: 0.9 μUnits/25 μg=0.036 mU/mg total protein (probably an over estimate)

MYXV infected RK13 cells 65.4 μUnits/1.6 μg=40.9 mU/mg total protein

Total sialyltransferase activity in 20 ml lysate contains 2.596 Units in 63.48 mg total protein isolated from 1.83 g of wet cells. Weinstein estimated that a rat liver (3.2 kg starting material) triton extract (20.8 liters; 68.5 g total protein) contained 9.9 units (specific activity 0.145 mUnits/mg) of α2,3-sialyltransferase (EC:2.4.99.6).

Conclusion

The myxoma virus and other members of the Leporipoxvirus genus encode a gene which belongs to the sialyltransferase family (ie it contains a sialyl motif CMP-SA binding site) being most closely related to the α2,3 Galβ1-3(4) GlcNAc sialyltransferase (EC:2.4.99.6). The myxoma virus MST3N gene encodes a protein of predicted MW of 33.3 kDa (non-glycosylated) being one of the smallest known sialyltransferase proteins. Basic characterisation of the sialyltransferase activity indicates that the enzyme has an α2,3 sialyltransferase activity towards N-glycan of glycoproteins suggesting an α2,3 Galβ1,3(4) GlcNAc sialyltransferase activity. Activity towards glycolipid acceptors has not been tested. Tissue culture cells infected with myxoma virus produce significant amounts of sialyltransferase activity by 24 hours post infection producing approximately a 280-fold specific activity than estimated can be obtained from rat the normal source of enzyme isolation. The relatively high level of expression and absence of other detectable sialyltransferase activities enables convenient purification by affinity chromatography using Cibacron Blue F3GA-Sepharoseand/or CDP-agarose.

EXAMPLE 2

Identification of candidate Poxvirus was undertaken using the set of degenerate primers: [SEQ ID NOS:1 & 2]

CAP-I GGGATCCAT[A/T/C]TC[T/C]AG[A/G]CA[T/C]AA[A/G]CG

CAP-II GGGATCCGC[A/G]CA[T/C]AA[A/T/C/G]CC[T/G/A]ATCAT

PCR-Reaction using Pfu polymerase (Stratagene) in 100 μl total volume

Poxvirus DNA (approximately 5 ng)

1×Pfu polymerase buffer (Stratagene)

CAP-I 1 μM

CAP-II 1 μM

NTP mixture 100 μM each

Pfu polymerase 2.5 Units (Stratagene)

30 cycles

94° C., 20 seconds

45° C., 1 minute

72° C., 30 seconds

final extension at 72° C. for 5 minutes

EXAMPLE 3

Scale-up and Purification of the Myxoma Virus Sialyltransferase

Stocks of myxoma virus, Lu, can be prepared on RK13 cells to titres of approximately 10⁷ pfu/ml. If necessary concentrated viral stocks (10⁸ -10⁹ pfu/ml) can be prepared by ultra-centrifugation of virus and re-suspension in an appropriate volume. Confluent roller bottle cultures of the most optimum cell type for sialyltransferase expression can be infected at a multiplicity of infection (MOI) of 1 or greater. Twenty-four to 48 hours post infection the cells can be harvested, washed in PBS and lysed using a Triton-MES buffer as described in the invention.

Affinity purification and concentration of the sialyltransferase may be performed by any suitable means known to the art, and in the present example by using a combination of CIBACRON BLUE 3GA-Sepharose 6B (Sticher et al, 1988, Biochem J 253:577) and CDP-Sepharose (Paulson et al, 1977, J Biol Chem, 252:2356) affinity chromatography.

It will of course be realised that while the above has been given by way of illustrative example of this invention, all such and other modifications and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of this invention as defined in the claims appended hereto.

    __________________________________________________________________________     #             SEQUENCE LISTING                                                    - -  - - <160> NUMBER OF SEQ ID NOS: 13                                        - - <210> SEQ ID NO 1                                                         <211> LENGTH: 24                                                               <212> TYPE: DNA                                                                <213> ORGANISM: Myxoma virus                                                    - - <400> SEQUENCE: 1                                                          - - gggatccath tcyagrcaya arcg          - #                  - #                     24                                                                      - -  - - <210> SEQ ID NO 2                                                    <211> LENGTH: 24                                                               <212> TYPE: DNA                                                                <213> ORGANISM: Myxoma virus                                                   <220> FEATURE:                                                                 <221> NAME/KEY: misc.sub.-- feature                                            <222> LOCATION: (16)..(24)                                                     <223> OTHER INFORMATION: Nucleotide at position 16 - # is n wherein                  n = a, t, c or g.                                                         - - <400> SEQUENCE: 2                                                          - - gggatccgcr cayaanccda tcat          - #                  - #                     24                                                                       - -  - - <210> SEQ ID NO 3                                                    <211> LENGTH: 4713                                                             <212> TYPE: DNA                                                                <213> ORGANISM: Myxoma virus                                                   <220> FEATURE:                                                                 <221> NAME/KEY: CDS                                                            <222> LOCATION: (1)..(549)                                                     <220> FEATURE:                                                                 <221> NAME/KEY: CDS                                                            <222> LOCATION: (1515)..(2081)                                                 <220> FEATURE:                                                                 <221> NAME/KEY: CDS                                                            <222> LOCATION: (2084)..(3745)                                                 <220> FEATURE:                                                                 <221> NAME/KEY: CDS                                                            <222> LOCATION: (3778)..(4434)                                                 <220> FEATURE:                                                                 <221> NAME/KEY: CDS                                                            <222> LOCATION: (4440)..(4712)                                                  - - <400> SEQUENCE: 3                                                          - - gga tcc aac gtc gtc gta tct gtg gcg ttg tt - #c gaa gaa gcg gag ggg            48                                                                        Gly Ser Asn Val Val Val Ser Val Ala Leu Ph - #e Glu Glu Ala Glu Gly              1               5 - #                 10 - #                 15               - - cct cgg gtt ccg tta ctc aga acg att cac aa - #c gga ggc gtt att atc            96                                                                        Pro Arg Val Pro Leu Leu Arg Thr Ile His As - #n Gly Gly Val Ile Ile                         20     - #             25     - #             30                   - - tcc aga cat aaa cgg ttg cat aag gaa ctc cc - #c agt caa gat tgg ttt           144                                                                        Ser Arg His Lys Arg Leu His Lys Glu Leu Pr - #o Ser Gln Asp Trp Phe                     35         - #         40         - #         45                       - - tct ttt tac gtg gaa gta ttc cac tgc tac ac - #t tcc gtg ata tac gcg           192                                                                        Ser Phe Tyr Val Glu Val Phe His Cys Tyr Th - #r Ser Val Ile Tyr Ala                 50             - #     55             - #     60                           - - gta gtt gac gga gcc gtt cta tac gca aac gc - #c gat tac aaa aca cat           240                                                                        Val Val Asp Gly Ala Val Leu Tyr Ala Asn Al - #a Asp Tyr Lys Thr His             65                 - # 70                 - # 75                 - # 80        - - tgt acg ata agc gat ggc cga cga cat agg ga - #a gac gtt acg gac gat           288                                                                        Cys Thr Ile Ser Asp Gly Arg Arg His Arg Gl - #u Asp Val Thr Asp Asp                             85 - #                 90 - #                 95               - - tgt ctg tgt tgt cac gta tct cct caa att cg - #t acg ttc ggt aca cag           336                                                                        Cys Leu Cys Cys His Val Ser Pro Gln Ile Ar - #g Thr Phe Gly Thr Gln                        100      - #           105      - #           110                   - - gta atg gag aac gta gag tgt cgg gtg gta cg - #g gat ggt tta tgt atc           384                                                                        Val Met Glu Asn Val Glu Cys Arg Val Val Ar - #g Asp Gly Leu Cys Ile                    115          - #       120          - #       125                       - - gaa ata aaa cac gtg gga aaa ttc gga gca tc - #g tgc gta ggt gcg tat           432                                                                        Glu Ile Lys His Val Gly Lys Phe Gly Ala Se - #r Cys Val Gly Ala Tyr                130              - #   135              - #   140                           - - aat acg cgg tat ata aaa ata gcg ata ggg tc - #g gtg tac gat atc att           480                                                                        Asn Thr Arg Tyr Ile Lys Ile Ala Ile Gly Se - #r Val Tyr Asp Ile Ile            145                 1 - #50                 1 - #55                 1 -       #60                                                                               - - cta aaa cag gac ggg atg tcc gga aag aag cg - #a cat agt tgc tac         gtg      528                                                                     Leu Lys Gln Asp Gly Met Ser Gly Lys Lys Ar - #g His Ser Cys Tyr Val                           165  - #               170  - #               175               - - tac gga atc acc cga cgg tag gcttgcgaaa tagtgtatt - #g ttttttatca              579                                                                        Tyr Gly Ile Thr Arg Arg                                                                    180                                                                 - - gagttagcgt atacaaagga tcgtcttatt ttggatcata cgttcgatga tc -              #gttttctc    639                                                                  - - cgcgtttacg tcgtgaatgg agttttgcat ggcacgcata gtatagccgt tg -             #taataatg    699                                                                  - - gataaattgg ttaggccccc cattggggta cccgaatccc gtaatcgtta cg -             #ccctggca    759                                                                  - - cacgtgtaac gcggtcacga gcgcgaccat tcccatcgta ggaacgtgca ac -             #gttccgga    819                                                                  - - cgttgtctgt atacgcaacg ccgcatcgta cgtatatttc ggatgtagga tt -             #cgtacgaa    879                                                                  - - cgccggacgc gcgcgccacg tgcgaggcgg tttcttccaa aatctagaca gg -             #tcgacgcg    939                                                                  - - tgcgttgttc gtaagcatgt tatatagcca gtataagtcg gcggacttga ac -             #ggaaccat    999                                                                  - - tacaaacagc gtcgtattat cgttttcttt cacggaatcc gattgggcgg at -             #tccgggta   1059                                                                  - - gaacatacgt atcgtcgttt ttgtcccaac gtctcgttcg aaggcacgaa cg -             #ggagcgtc   1119                                                                  - - gtttaaccga aacaccacgt tgtacgagtc gatgattcgt cctaaagatc ta -             #ttgtgtaa   1179                                                                  - - gttataacta tttcctacga cgatacattg tttgccgtat aagaggaaat ta -             #ggaagatg   1239                                                                  - - tccaggaatc ttttctaaca gacgacgtat ctgcgcttcc tctcctttta gc -             #ccgtacgg   1299                                                                  - - taaacgtctt tcgaacgtat tattgtgggt tacaaatacg tttgtgacgg at -             #acgttgtt   1359                                                                  - - cgttccgtgg tttaccacgg acattttcaa cgacattacg aacaacgcaa ct -             #gcggtaca   1419                                                                  - - tgcgtacacc atcgtgcatc gtttaaagaa atacatatcg cagaagcaag at -             #tttttttg   1479                                                                  - - tgttttagtc tacccaacgt acgcgataga acact atg agc aac - #tac gta aag           1532                                                                                          - #                  - #   Met Ser Asn Tyr Val Lys                             - #                  - #       185                            - - ttc gac gta tcg atc gaa gat gac tgt atc aa - #t ata acg gtc agt aac          1580                                                                        Phe Asp Val Ser Ile Glu Asp Asp Cys Ile As - #n Ile Thr Val Ser Asn            190                 1 - #95                 2 - #00                 2 -       #05                                                                               - - act agt tta ccc atc cac gta aag acc gtc cc - #c aaa cgc aca cat         cgg     1628                                                                     Thr Ser Leu Pro Ile His Val Lys Thr Val Pr - #o Lys Arg Thr His Arg                           210  - #               215  - #               220               - - gac aat tac gtg ttt aaa aac act ata gac gc - #c tcg gac gat atc gtc          1676                                                                        Asp Asn Tyr Val Phe Lys Asn Thr Ile Asp Al - #a Ser Asp Asp Ile Val                        225      - #           230      - #           235                   - - tct atc cta cac aac tat ata tgg tac aga gg - #a ttt ata ggt ctg ccg          1724                                                                        Ser Ile Leu His Asn Tyr Ile Trp Tyr Arg Gl - #y Phe Ile Gly Leu Pro                    240          - #       245          - #       250                       - - aac aaa tac ggt agg gtg ttc aaa gaa cta aa - #g ctc ttc gac atc gac          1772                                                                        Asn Lys Tyr Gly Arg Val Phe Lys Glu Leu Ly - #s Leu Phe Asp Ile Asp                255              - #   260              - #   265                           - - gca aag acc aaa tac gga gat ata aat act tt - #a ttt ttc atg tta aat          1820                                                                        Ala Lys Thr Lys Tyr Gly Asp Ile Asn Thr Le - #u Phe Phe Met Leu Asn            270                 2 - #75                 2 - #80                 2 -       #85                                                                               - - tta aac tcg gat cgt tgc tgc agg aat ttt tt - #c aat ttc gta aca         cta     1868                                                                     Leu Asn Ser Asp Arg Cys Cys Arg Asn Phe Ph - #e Asn Phe Val Thr Leu                           290  - #               295  - #               300               - - caa aaa act ata ttc aaa cac acg gtt acc gt - #a tac aac tgc atc gaa          1916                                                                        Gln Lys Thr Ile Phe Lys His Thr Val Thr Va - #l Tyr Asn Cys Ile Glu                        305      - #           310      - #           315                   - - atg ata gga tta tgt gcc ctg gtg gcg gaa ca - #a tgg aaa aat aat aac          1964                                                                        Met Ile Gly Leu Cys Ala Leu Val Ala Glu Gl - #n Trp Lys Asn Asn Asn                    320          - #       325          - #       330                       - - aaa tgt tta aat tgg cgt atc gta gta gat ga - #a atg ttt agg ttc atc          2012                                                                        Lys Cys Leu Asn Trp Arg Ile Val Val Asp Gl - #u Met Phe Arg Phe Ile                335              - #   340              - #   345                           - - gac cct gac atg tta gaa aag atc aga acg gt - #a ctc caa gaa cga ttg          2060                                                                        Asp Pro Asp Met Leu Glu Lys Ile Arg Thr Va - #l Leu Gln Glu Arg Leu            350                 3 - #55                 3 - #60                 3 -       #65                                                                               - - gcg tac gag gac ctg tcg taa ca atg acg ggt - # cgt tac gcc atc cgg           2107                                                                       Ala Tyr Glu Asp Leu Ser        Me - #t Thr Gly Arg Tyr Ala Ile Arg                             370  - #                  - #375                 - #380         - - ttg tta gaa tcc att aga aat tta cag gat aa - #g acc acc tta tgc gac          2155                                                                        Leu Leu Glu Ser Ile Arg Asn Leu Gln Asp Ly - #s Thr Thr Leu Cys Asp                            385  - #               390  - #               395               - - gtt acg tta gtt acg gac gat gat gtg tct at - #a cat gcg cat aaa ctt          2203                                                                        Val Thr Leu Val Thr Asp Asp Asp Val Ser Il - #e His Ala His Lys Leu                        400      - #           405      - #           410                   - - atc ttg tcc gcg tct tct acg tat ttc gaa ta - #t atg ttt tcg cac gac          2251                                                                        Ile Leu Ser Ala Ser Ser Thr Tyr Phe Glu Ty - #r Met Phe Ser His Asp                    415          - #       420          - #       425                       - - ttt ata gaa aaa gac aga aac gta ata aac gt - #g tgt gtc gaa tat cgt          2299                                                                        Phe Ile Glu Lys Asp Arg Asn Val Ile Asn Va - #l Cys Val Glu Tyr Arg                430              - #   435              - #   440                           - - gcc ttg ttg cac cta atc aat ttt ata tac tc - #a gga acc tta cgt ttg          2347                                                                        Ala Leu Leu His Leu Ile Asn Phe Ile Tyr Se - #r Gly Thr Leu Arg Leu            445                 4 - #50                 4 - #55                 4 -       #60                                                                               - - acg gat gat acg gtg gac tgt att cta gta gc - #c gcc gat tac cta         cag     2395                                                                     Thr Asp Asp Thr Val Asp Cys Ile Leu Val Al - #a Ala Asp Tyr Leu Gln                           465  - #               470  - #               475               - - ata cta gag gcg agt gaa ttg gcg gaa aac tt - #t ata ctc gcc cgt cta          2443                                                                        Ile Leu Glu Ala Ser Glu Leu Ala Glu Asn Ph - #e Ile Leu Ala Arg Leu                        480      - #           485      - #           490                   - - aga gcg gag aat tgc ctc cat tac tac gaa tt - #t tcc aaa cgt tac aac          2491                                                                        Arg Ala Glu Asn Cys Leu His Tyr Tyr Glu Ph - #e Ser Lys Arg Tyr Asn                    495          - #       500          - #       505                       - - aga cga cat ata ttc aac gtg gta atc acg ac - #g att ata cac aac atc          2539                                                                        Arg Arg His Ile Phe Asn Val Val Ile Thr Th - #r Ile Ile His Asn Ile                510              - #   515              - #   520                           - - gtc agt gtg tta aga caa ccc aat ttt aag ac - #c atc gag tta tgc gat          2587                                                                        Val Ser Val Leu Arg Gln Pro Asn Phe Lys Th - #r Ile Glu Leu Cys Asp            525                 5 - #30                 5 - #35                 5 -       #40                                                                               - - ctg cag aat ata tta tcc agc gac gat tta aa - #c gtg ata gac gag         gat     2635                                                                     Leu Gln Asn Ile Leu Ser Ser Asp Asp Leu As - #n Val Ile Asp Glu Asp                           545  - #               550  - #               555               - - gta tgc gcc gtc gtc tta gtc acc tgg ttg aa - #g caa aac aac atg gaa          2683                                                                        Val Cys Ala Val Val Leu Val Thr Trp Leu Ly - #s Gln Asn Asn Met Glu                        560      - #           565      - #           570                   - - gat tgc cca tcc gtt tta ctg gaa caa gta cg - #g atg tcg tta ctc tca          2731                                                                        Asp Cys Pro Ser Val Leu Leu Glu Gln Val Ar - #g Met Ser Leu Leu Ser                    575          - #       580          - #       585                       - - atg tct gtg aaa aac ctt cta cta aaa acc cc - #t tgc ata cgt aat aaa          2779                                                                        Met Ser Val Lys Asn Leu Leu Leu Lys Thr Pr - #o Cys Ile Arg Asn Lys                590              - #   595              - #   600                           - - cga tac gta cag tct ctc gcc aaa tta gac ca - #t tcc cct aga cct ccc          2827                                                                        Arg Tyr Val Gln Ser Leu Ala Lys Leu Asp Hi - #s Ser Pro Arg Pro Pro            605                 6 - #10                 6 - #15                 6 -       #20                                                                               - - act cag ggg tgt atc ctg tcg ata ggg ggt cg - #t aaa tac tac gac         gat     2875                                                                     Thr Gln Gly Cys Ile Leu Ser Ile Gly Gly Ar - #g Lys Tyr Tyr Asp Asp                           625  - #               630  - #               635               - - atc acg tcc agt ccc gta gaa ttg tat tct cc - #c gtg gac gac gta tgg          2923                                                                        Ile Thr Ser Ser Pro Val Glu Leu Tyr Ser Pr - #o Val Asp Asp Val Trp                        640      - #           645      - #           650                   - - acg acc gtg tcc tac tta cca acg cac cga ca - #g ttc ttt agc gtc gcc          2971                                                                        Thr Thr Val Ser Tyr Leu Pro Thr His Arg Gl - #n Phe Phe Ser Val Ala                    655          - #       660          - #       665                       - - gta ttg gat ttt gtc gta tac gtc gtg ggt gg - #g tta cag gac agt gta          3019                                                                        Val Leu Asp Phe Val Val Tyr Val Val Gly Gl - #y Leu Gln Asp Ser Val                670              - #   675              - #   680                           - - tcc gtc gcg tcc gtg tcc agt tac gac gta aa - #g acg aac gaa tgg aaa          3067                                                                        Ser Val Ala Ser Val Ser Ser Tyr Asp Val Ly - #s Thr Asn Glu Trp Lys            685                 6 - #90                 6 - #95                 7 -       #00                                                                               - - gag tgt cct cct ctt aaa agt ccc cga cac gg - #g tgc gga tta gtg         gtc     3115                                                                     Glu Cys Pro Pro Leu Lys Ser Pro Arg His Gl - #y Cys Gly Leu Val Val                           705  - #               710  - #               715               - - ttg cga gac aaa ctg ata gtg ata gga gga aa - #a gga aga aac tcc tat          3163                                                                        Leu Arg Asp Lys Leu Ile Val Ile Gly Gly Ly - #s Gly Arg Asn Ser Tyr                        720      - #           725      - #           730                   - - ctg aaa gac gtc gac tac tgg aga ccg acg ta - #c gcc acg tgg aga aaa          3211                                                                        Leu Lys Asp Val Asp Tyr Trp Arg Pro Thr Ty - #r Ala Thr Trp Arg Lys                    735          - #       740          - #       745                       - - ctg tgc tct ctc cgc gag gcg agg acg aac gt - #g gga gcc gcc gtc gta          3259                                                                        Leu Cys Ser Leu Arg Glu Ala Arg Thr Asn Va - #l Gly Ala Ala Val Val                750              - #   755              - #   760                           - - cgc aac aaa gtc tat aca ata ggc ggg ata cg - #t agc gtc gag gaa ccg          3307                                                                        Arg Asn Lys Val Tyr Thr Ile Gly Gly Ile Ar - #g Ser Val Glu Glu Pro            765                 7 - #70                 7 - #75                 7 -       #80                                                                               - - agt cga ttg gaa tgc atc gat acc gta gag tg - #t tta cag aac aac         aaa     3355                                                                     Ser Arg Leu Glu Cys Ile Asp Thr Val Glu Cy - #s Leu Gln Asn Asn Lys                           785  - #               790  - #               795               - - tgg gtc gcg aag aag tcg tta ccc gaa cca aa - #g gcc tgt ttg gcc gtg          3403                                                                        Trp Val Ala Lys Lys Ser Leu Pro Glu Pro Ly - #s Ala Cys Leu Ala Val                        800      - #           805      - #           810                   - - gcg cct tac aaa cat ttc att tac gcg gcg gg - #t gga tac gcc atc aac          3451                                                                        Ala Pro Tyr Lys His Phe Ile Tyr Ala Ala Gl - #y Gly Tyr Ala Ile Asn                    815          - #       820          - #       825                       - - ggc agg ggc acc gtc gtt act aaa acg aac ac - #g ttg tac atg tat aac          3499                                                                        Gly Arg Gly Thr Val Val Thr Lys Thr Asn Th - #r Leu Tyr Met Tyr Asn                830              - #   835              - #   840                           - - gtg gaa ttg gac gac tgg ttt tac cta cct at - #g atg gag ctg tct aga          3547                                                                        Val Glu Leu Asp Asp Trp Phe Tyr Leu Pro Me - #t Met Glu Leu Ser Arg            845                 8 - #50                 8 - #55                 8 -       #60                                                                               - - aac gac gcg tct ctc tgt gtg tta ggt aaa ga - #c ctc tac gtt gta         ggg     3595                                                                     Asn Asp Ala Ser Leu Cys Val Leu Gly Lys As - #p Leu Tyr Val Val Gly                           865  - #               870  - #               875               - - ggt ttt gta gga tcg gga tac aca aat tcc gt - #g gaa aaa tac aac cac          3643                                                                        Gly Phe Val Gly Ser Gly Tyr Thr Asn Ser Va - #l Glu Lys Tyr Asn His                        880      - #           885      - #           890                   - - aag acc aat aat tgg gaa cga att ata cca tg - #t aaa tcg ccc aag tac          3691                                                                        Lys Thr Asn Asn Trp Glu Arg Ile Ile Pro Cy - #s Lys Ser Pro Lys Tyr                    895          - #       900          - #       905                       - - gga cac tgt tcc gtc gtg tta aac cac gag tg - #c cct tgg aaa cat ctg          3739                                                                        Gly His Cys Ser Val Val Leu Asn His Glu Cy - #s Pro Trp Lys His Leu                910              - #   915              - #   920                           - - cgc taa aaactaaaat ataacgcgga agaagagaga cg atg cgt - # gtg tta agt          3792                                                                        Arg                  - #                  - #     Met Arg Val Leu Ser          925                  - #                  - #                 930               - - att tta gcg tta tta tct aca gta gcc tac gc - #t tac tcc gtt cgc tgt          3840                                                                        Ile Leu Ala Leu Leu Ser Thr Val Ala Tyr Al - #a Tyr Ser Val Arg Cys                        935      - #           940      - #           945                   - - aca aat aca acg acg gta gcc gaa cat gta aa - #c gtt act att agt tgc          3888                                                                        Thr Asn Thr Thr Thr Val Ala Glu His Val As - #n Val Thr Ile Ser Cys                    950          - #       955          - #       960                       - - aat aaa act agc agt agt agt agt ttg ttc ca - #t ctt ata acg tgg aaa          3936                                                                        Asn Lys Thr Ser Ser Ser Ser Ser Leu Phe Hi - #s Leu Ile Thr Trp Lys                965              - #   970              - #   975                           - - aaa aat aat gaa acg act ata gcg ggg tac gg - #a cca agt ggc gca acc          3984                                                                        Lys Asn Asn Glu Thr Thr Ile Ala Gly Tyr Gl - #y Pro Ser Gly Ala Thr            980                 9 - #85                 9 - #90                 9 -       #95                                                                               - - att aaa gat gcg agc aaa ata gag tat tta tc - #c act gga tac aac         acg     4032                                                                     Ile Lys Asp Ala Ser Lys Ile Glu Tyr Leu Se - #r Thr Gly Tyr Asn Thr                          1000  - #              1005   - #             1010               - - tcc act atc ttg ata aaa aat gta agc gcg ga - #a gat agc gga ctt tac          4080                                                                        Ser Thr Ile Leu Ile Lys Asn Val Ser Ala Gl - #u Asp Ser Gly Leu Tyr                       1015      - #          1020       - #         1025                   - - tac tgt ata ttc aac tcg ttc tct acc gaa cc - #t agc gaa gaa gga acg          4128                                                                        Tyr Cys Ile Phe Asn Ser Phe Ser Thr Glu Pr - #o Ser Glu Glu Gly Thr                   1030          - #      1035           - #     1040                       - - gta cgg gta aac gta acg aca tct agt gca ac - #g act act tta caa caa          4176                                                                        Val Arg Val Asn Val Thr Thr Ser Ser Ala Th - #r Thr Thr Leu Gln Gln               1045              - #  1050               - # 1055                           - - cct caa cct cag gct tta cga acg acc cgt gg - #t cga tcg act aat cga          4224                                                                        Pro Gln Pro Gln Ala Leu Arg Thr Thr Arg Gl - #y Arg Ser Thr Asn Arg            1060               1065 - #               1070  - #              1075           - - tcg acg tcg cgt cac gta tcg cgt acc tcg ac - #g cat cac gta ggt gac          4272                                                                        Ser Thr Ser Arg His Val Ser Arg Thr Ser Th - #r His His Val Gly Asp                           1080  - #              1085   - #             1090               - - gga tcc tta acg gtg gaa acg aga cag tat aa - #a tac tca tct tcg tcc          4320                                                                        Gly Ser Leu Thr Val Glu Thr Arg Gln Tyr Ly - #s Tyr Ser Ser Ser Ser                       1095      - #          1100       - #         1105                   - - tct tcc tca tcc tcc agc tgg acg agt agc gc - #a gga tct cgt aac gta          4368                                                                        Ser Ser Ser Ser Ser Ser Trp Thr Ser Ser Al - #a Gly Ser Arg Asn Val                   1110          - #      1115           - #     1120                       - - ccg agc tta ttt aaa ctc att ttc gta ata aa - #a atg att ttt tat atc          4416                                                                        Pro Ser Leu Phe Lys Leu Ile Phe Val Ile Ly - #s Met Ile Phe Tyr Ile               1125              - #  1130               - # 1135                           - - cca aat tta atc gga taa atact atg tca aaa - #cga aac gaa ata gaa         cca   4466                                                                       Pro Asn Leu Ile Gly           - #Met Ser Lys Arg Asn Glu Ile Glu Pro          1140               1145 - #                  - #   1150                         - - ggg gac gtg tta atc gat gca tcg aaa cgg ga - #a tgg gta ctc ggg gac          4514                                                                        Gly Asp Val Leu Ile Asp Ala Ser Lys Arg Gl - #u Trp Val Leu Gly Asp            1155               1160 - #               1165  - #              1170           - - att ttg gga aag ggt ggg ttt gga tac att ta - #c acg gcc cgt ttg tgt          4562                                                                        Ile Leu Gly Lys Gly Gly Phe Gly Tyr Ile Ty - #r Thr Ala Arg Leu Cys                           1175  - #              1180   - #             1185               - - tcg gaa gag gaa ttt gac aaa tac gtt ata aa - #a ata gaa ccg aaa agt          4610                                                                        Ser Glu Glu Glu Phe Asp Lys Tyr Val Ile Ly - #s Ile Glu Pro Lys Ser                       1190      - #          1195       - #         1200                   - - aac ggt ccc ttg ttc gta gaa cag gtg ttt ta - #t caa cgg gtg ggt aaa          4658                                                                        Asn Gly Pro Leu Phe Val Glu Gln Val Phe Ty - #r Gln Arg Val Gly Lys                   1205          - #      1210           - #     1215                       - - acc gac atg gtc acg gac tgg tgt aag aaa aa - #t aac tta ccg tat ttg          4706                                                                        Thr Asp Met Val Thr Asp Trp Cys Lys Lys As - #n Asn Leu Pro Tyr Leu               1220              - #  1225               - # 1230                           - - gga att c               - #                  - #                  -      #        4713                                                                   Gly Ile                                                                        1235                                                                            - -  - - <210> SEQ ID NO 4                                                    <211> LENGTH: 182                                                              <212> TYPE: PRT                                                                <213> ORGANISM: Myxoma virus                                                    - - <400> SEQUENCE: 4                                                          - - Gly Ser Asn Val Val Val Ser Val Ala Leu Ph - #e Glu Glu Ala Glu Gly         1               5 - #                 10 - #                 15               - - Pro Arg Val Pro Leu Leu Arg Thr Ile His As - #n Gly Gly Val Ile Ile                    20     - #             25     - #             30                   - - Ser Arg His Lys Arg Leu His Lys Glu Leu Pr - #o Ser Gln Asp Trp Phe                35         - #         40         - #         45                       - - Ser Phe Tyr Val Glu Val Phe His Cys Tyr Th - #r Ser Val Ile Tyr Ala            50             - #     55             - #     60                           - - Val Val Asp Gly Ala Val Leu Tyr Ala Asn Al - #a Asp Tyr Lys Thr His        65                 - # 70                 - # 75                 - # 80        - - Cys Thr Ile Ser Asp Gly Arg Arg His Arg Gl - #u Asp Val Thr Asp Asp                        85 - #                 90 - #                 95               - - Cys Leu Cys Cys His Val Ser Pro Gln Ile Ar - #g Thr Phe Gly Thr Gln                   100      - #           105      - #           110                   - - Val Met Glu Asn Val Glu Cys Arg Val Val Ar - #g Asp Gly Leu Cys Ile               115          - #       120          - #       125                       - - Glu Ile Lys His Val Gly Lys Phe Gly Ala Se - #r Cys Val Gly Ala Tyr           130              - #   135              - #   140                           - - Asn Thr Arg Tyr Ile Lys Ile Ala Ile Gly Se - #r Val Tyr Asp Ile Ile       145                 1 - #50                 1 - #55                 1 -       #60                                                                               - - Leu Lys Gln Asp Gly Met Ser Gly Lys Lys Ar - #g His Ser Cys Tyr         Val                                                                                              165  - #               170  - #               175              - - Tyr Gly Ile Thr Arg Arg                                                               180                                                                 - -  - - <210> SEQ ID NO 5                                                    <211> LENGTH: 188                                                              <212> TYPE: PRT                                                                <213> ORGANISM: Myxoma virus                                                    - - <400> SEQUENCE: 5                                                          - - Met Ser Asn Tyr Val Lys Phe Asp Val Ser Il - #e Glu Asp Asp Cys Ile         1               5 - #                 10 - #                 15               - - Asn Ile Thr Val Ser Asn Thr Ser Leu Pro Il - #e His Val Lys Thr Val                    20     - #             25     - #             30                   - - Pro Lys Arg Thr His Arg Asp Asn Tyr Val Ph - #e Lys Asn Thr Ile Asp                35         - #         40         - #         45                       - - Ala Ser Asp Asp Ile Val Ser Ile Leu His As - #n Tyr Ile Trp Tyr Arg            50             - #     55             - #     60                           - - Gly Phe Ile Gly Leu Pro Asn Lys Tyr Gly Ar - #g Val Phe Lys Glu Leu        65                 - # 70                 - # 75                 - # 80        - - Lys Leu Phe Asp Ile Asp Ala Lys Thr Lys Ty - #r Gly Asp Ile Asn Thr                        85 - #                 90 - #                 95               - - Leu Phe Phe Met Leu Asn Leu Asn Ser Asp Ar - #g Cys Cys Arg Asn Phe                   100      - #           105      - #           110                   - - Phe Asn Phe Val Thr Leu Gln Lys Thr Ile Ph - #e Lys His Thr Val Thr               115          - #       120          - #       125                       - - Val Tyr Asn Cys Ile Glu Met Ile Gly Leu Cy - #s Ala Leu Val Ala Glu           130              - #   135              - #   140                           - - Gln Trp Lys Asn Asn Asn Lys Cys Leu Asn Tr - #p Arg Ile Val Val Asp       145                 1 - #50                 1 - #55                 1 -       #60                                                                               - - Glu Met Phe Arg Phe Ile Asp Pro Asp Met Le - #u Glu Lys Ile Arg         Thr                                                                                              165  - #               170  - #               175              - - Val Leu Gln Glu Arg Leu Ala Tyr Glu Asp Le - #u Ser                                   180      - #           185                                          - -  - - <210> SEQ ID NO 6                                                    <211> LENGTH: 553                                                              <212> TYPE: PRT                                                                <213> ORGANISM: Myxoma virus                                                    - - <400> SEQUENCE: 6                                                          - - Met Thr Gly Arg Tyr Ala Ile Arg Leu Leu Gl - #u Ser Ile Arg Asn Leu         1               5 - #                 10 - #                 15               - - Gln Asp Lys Thr Thr Leu Cys Asp Val Thr Le - #u Val Thr Asp Asp Asp                    20     - #             25     - #             30                   - - Val Ser Ile His Ala His Lys Leu Ile Leu Se - #r Ala Ser Ser Thr Tyr                35         - #         40         - #         45                       - - Phe Glu Tyr Met Phe Ser His Asp Phe Ile Gl - #u Lys Asp Arg Asn Val            50             - #     55             - #     60                           - - Ile Asn Val Cys Val Glu Tyr Arg Ala Leu Le - #u His Leu Ile Asn Phe        65                 - # 70                 - # 75                 - # 80        - - Ile Tyr Ser Gly Thr Leu Arg Leu Thr Asp As - #p Thr Val Asp Cys Ile                        85 - #                 90 - #                 95               - - Leu Val Ala Ala Asp Tyr Leu Gln Ile Leu Gl - #u Ala Ser Glu Leu Ala                   100      - #           105      - #           110                   - - Glu Asn Phe Ile Leu Ala Arg Leu Arg Ala Gl - #u Asn Cys Leu His Tyr               115          - #       120          - #       125                       - - Tyr Glu Phe Ser Lys Arg Tyr Asn Arg Arg Hi - #s Ile Phe Asn Val Val           130              - #   135              - #   140                           - - Ile Thr Thr Ile Ile His Asn Ile Val Ser Va - #l Leu Arg Gln Pro Asn       145                 1 - #50                 1 - #55                 1 -       #60                                                                               - - Phe Lys Thr Ile Glu Leu Cys Asp Leu Gln As - #n Ile Leu Ser Ser         Asp                                                                                              165  - #               170  - #               175              - - Asp Leu Asn Val Ile Asp Glu Asp Val Cys Al - #a Val Val Leu Val Thr                   180      - #           185      - #           190                   - - Trp Leu Lys Gln Asn Asn Met Glu Asp Cys Pr - #o Ser Val Leu Leu Glu               195          - #       200          - #       205                       - - Gln Val Arg Met Ser Leu Leu Ser Met Ser Va - #l Lys Asn Leu Leu Leu           210              - #   215              - #   220                           - - Lys Thr Pro Cys Ile Arg Asn Lys Arg Tyr Va - #l Gln Ser Leu Ala Lys       225                 2 - #30                 2 - #35                 2 -       #40                                                                               - - Leu Asp His Ser Pro Arg Pro Pro Thr Gln Gl - #y Cys Ile Leu Ser         Ile                                                                                              245  - #               250  - #               255              - - Gly Gly Arg Lys Tyr Tyr Asp Asp Ile Thr Se - #r Ser Pro Val Glu Leu                   260      - #           265      - #           270                   - - Tyr Ser Pro Val Asp Asp Val Trp Thr Thr Va - #l Ser Tyr Leu Pro Thr               275          - #       280          - #       285                       - - His Arg Gln Phe Phe Ser Val Ala Val Leu As - #p Phe Val Val Tyr Val           290              - #   295              - #   300                           - - Val Gly Gly Leu Gln Asp Ser Val Ser Val Al - #a Ser Val Ser Ser Tyr       305                 3 - #10                 3 - #15                 3 -       #20                                                                               - - Asp Val Lys Thr Asn Glu Trp Lys Glu Cys Pr - #o Pro Leu Lys Ser         Pro                                                                                              325  - #               330  - #               335              - - Arg His Gly Cys Gly Leu Val Val Leu Arg As - #p Lys Leu Ile Val Ile                   340      - #           345      - #           350                   - - Gly Gly Lys Gly Arg Asn Ser Tyr Leu Lys As - #p Val Asp Tyr Trp Arg               355          - #       360          - #       365                       - - Pro Thr Tyr Ala Thr Trp Arg Lys Leu Cys Se - #r Leu Arg Glu Ala Arg           370              - #   375              - #   380                           - - Thr Asn Val Gly Ala Ala Val Val Arg Asn Ly - #s Val Tyr Thr Ile Gly       385                 3 - #90                 3 - #95                 4 -       #00                                                                               - - Gly Ile Arg Ser Val Glu Glu Pro Ser Arg Le - #u Glu Cys Ile Asp         Thr                                                                                              405  - #               410  - #               415              - - Val Glu Cys Leu Gln Asn Asn Lys Trp Val Al - #a Lys Lys Ser Leu Pro                   420      - #           425      - #           430                   - - Glu Pro Lys Ala Cys Leu Ala Val Ala Pro Ty - #r Lys His Phe Ile Tyr               435          - #       440          - #       445                       - - Ala Ala Gly Gly Tyr Ala Ile Asn Gly Arg Gl - #y Thr Val Val Thr Lys           450              - #   455              - #   460                           - - Thr Asn Thr Leu Tyr Met Tyr Asn Val Glu Le - #u Asp Asp Trp Phe Tyr       465                 4 - #70                 4 - #75                 4 -       #80                                                                               - - Leu Pro Met Met Glu Leu Ser Arg Asn Asp Al - #a Ser Leu Cys Val         Leu                                                                                              485  - #               490  - #               495              - - Gly Lys Asp Leu Tyr Val Val Gly Gly Phe Va - #l Gly Ser Gly Tyr Thr                   500      - #           505      - #           510                   - - Asn Ser Val Glu Lys Tyr Asn His Lys Thr As - #n Asn Trp Glu Arg Ile               515          - #       520          - #       525                       - - Ile Pro Cys Lys Ser Pro Lys Tyr Gly His Cy - #s Ser Val Val Leu Asn           530              - #   535              - #   540                           - - His Glu Cys Pro Trp Lys His Leu Arg                                       545                 5 - #50                                                     - -  - - <210> SEQ ID NO 7                                                    <211> LENGTH: 218                                                              <212> TYPE: PRT                                                                <213> ORGANISM: Myxoma virus                                                    - - <400> SEQUENCE: 7                                                          - -             Met Arg Val Leu - # Ser Ile Leu Ala Leu Leu Ser Thr Val                   1      - #         5         - #          10                        - - Ala Tyr Ala Tyr Ser Val Arg Cys Thr Asn Th - #r Thr Thr Val Ala Glu            15             - #     20             - #     25                           - - His Val Asn Val Thr Ile Ser Cys Asn Lys Th - #r Ser Ser Ser Ser Ser        30                 - # 35                 - # 40                 - # 45        - - Leu Phe His Leu Ile Thr Trp Lys Lys Asn As - #n Glu Thr Thr Ile Ala                        50 - #                 55 - #                 60               - - Gly Tyr Gly Pro Ser Gly Ala Thr Ile Lys As - #p Ala Ser Lys Ile Glu                    65     - #             70     - #             75                   - - Tyr Leu Ser Thr Gly Tyr Asn Thr Ser Thr Il - #e Leu Ile Lys Asn Val                80         - #         85         - #         90                       - - Ser Ala Glu Asp Ser Gly Leu Tyr Tyr Cys Il - #e Phe Asn Ser Phe Ser            95             - #    100             - #    105                           - - Thr Glu Pro Ser Glu Glu Gly Thr Val Arg Va - #l Asn Val Thr Thr Ser       110                 1 - #15                 1 - #20                 1 -       #25                                                                               - - Ser Ala Thr Thr Thr Leu Gln Gln Pro Gln Pr - #o Gln Ala Leu Arg         Thr                                                                                              130  - #               135  - #               140              - - Thr Arg Gly Arg Ser Thr Asn Arg Ser Thr Se - #r Arg His Val Ser Arg                   145      - #           150      - #           155                   - - Thr Ser Thr His His Val Gly Asp Gly Ser Le - #u Thr Val Glu Thr Arg               160          - #       165          - #       170                       - - Gln Tyr Lys Tyr Ser Ser Ser Ser Ser Ser Se - #r Ser Ser Ser Trp Thr           175              - #   180              - #   185                           - - Ser Ser Ala Gly Ser Arg Asn Val Pro Ser Le - #u Phe Lys Leu Ile Phe       190                 1 - #95                 2 - #00                 2 -       #05                                                                               - - Val Ile Lys Met Ile Phe Tyr Ile Pro Asn Le - #u Ile Gly                                   210  - #               215                                      - -  - - <210> SEQ ID NO 8                                                    <211> LENGTH: 91                                                               <212> TYPE: PRT                                                                <213> ORGANISM: Myxoma virus                                                    - - <400> SEQUENCE: 8                                                          - -     Met Ser Lys Arg Asn Glu Ile Glu - #Pro Gly Asp Val Leu Ile Asp           1              - # 5                 - #  10                - #  15         - - Ala Ser Lys Arg Glu Trp Val Leu Gly Asp Il - #e Leu Gly Lys Gly Gly                       20  - #                25  - #                30                - - Phe Gly Tyr Ile Tyr Thr Ala Arg Leu Cys Se - #r Glu Glu Glu Phe Asp                   35      - #            40      - #            45                    - - Lys Tyr Val Ile Lys Ile Glu Pro Lys Ser As - #n Gly Pro Leu Phe Val               50          - #        55          - #        60                        - - Glu Gln Val Phe Tyr Gln Arg Val Gly Lys Th - #r Asp Met Val Thr Asp           65              - #    70              - #    75                            - - Trp Cys Lys Lys Asn Asn Leu Pro Tyr Leu Gl - #y Ile                       80                  - #85                  - #90                                - -  - - <210> SEQ ID NO 9                                                    <211> LENGTH: 290                                                              <212> TYPE: PRT                                                                <213> ORGANISM: Myxoma virus                                                    - - <400> SEQUENCE: 9                                                          - - Met Tyr Phe Phe Lys Arg Cys Thr Met Val Ty - #r Ala Cys Thr Ala Val         1               5 - #                 10 - #                 15               - - Ala Leu Phe Val Met Ser Leu Lys Met Ser Va - #l Val Asn His Gly Thr                    20     - #             25     - #             30                   - - Asn Asn Val Ser Val Thr Asn Val Phe Val Th - #r His Asn Asn Thr Phe                35         - #         40         - #         45                       - - Glu Arg Arg Leu Pro Tyr Gly Leu Lys Gly Gl - #u Glu Ala Gln Ile Arg            50             - #     55             - #     60                           - - Arg Leu Leu Glu Lys Ile Pro Gly His Leu Pr - #o Asn Phe Leu Leu Tyr        65                 - # 70                 - # 75                 - # 80        - - Gly Lys Gln Cys Ile Val Val Gly Asn Ser Ty - #r Asn Leu His Asn Arg                        85 - #                 90 - #                 95               - - Ser Leu Gly Arg Ile Ile Asp Ser Tyr Asn Va - #l Val Phe Arg Leu Asn                   100      - #           105      - #           110                   - - Asp Ala Pro Val Arg Ala Phe Glu Arg Asp Va - #l Gly Thr Lys Thr Thr               115          - #       120          - #       125                       - - Ile Arg Met Phe Tyr Pro Glu Ser Ala Gln Se - #r Asp Ser Val Lys Glu           130              - #   135              - #   140                           - - Asn Asp Asn Thr Thr Leu Phe Val Met Val Pr - #o Phe Lys Ser Ala Asp       145                 1 - #50                 1 - #55                 1 -       #60                                                                               - - Leu Tyr Trp Leu Tyr Asn Met Leu Thr Asn As - #n Ala Arg Val Asp         Leu                                                                                              165  - #               170  - #               175              - - Ser Arg Phe Trp Lys Lys Pro Pro Arg Thr Tr - #p Arg Ala Arg Pro Ala                   180      - #           185      - #           190                   - - Phe Val Arg Ile Leu His Pro Lys Tyr Thr Ty - #r Asp Ala Ala Leu Arg               195          - #       200          - #       205                       - - Ile Gln Thr Thr Ser Gly Thr Leu His Val Pr - #o Thr Met Gly Met Val           210              - #   215              - #   220                           - - Ala Leu Val Thr Ala Leu His Val Cys Gln Gl - #y Val Thr Ile Thr Gly       225                 2 - #30                 2 - #35                 2 -       #40                                                                               - - Phe Gly Tyr Pro Asn Gly Gly Pro Asn Gln Ph - #e Ile His Tyr Tyr         Asn                                                                                              245  - #               250  - #               255              - - Gly Tyr Thr Met Arg Ala Met Gln Asn Ser Il - #e His Asp Val Asn Ala                   260      - #           265      - #           270                   - - Glu Lys Thr Ile Ile Glu Arg Met Ile Gln As - #n Lys Thr Ile Leu Cys               275          - #       280          - #       285                       - - Ile Arg                                                                       290                                                                         - -  - - <210> SEQ ID NO 10                                                   <211> LENGTH: 1806                                                             <212> TYPE: DNA                                                                <213> ORGANISM: Myxoma virus                                                   <220> FEATURE:                                                                 <221> NAME/KEY: CDS                                                            <222> LOCATION: (2)..(439)                                                     <220> FEATURE:                                                                 <221> NAME/KEY: CDS                                                            <222> LOCATION: (1405)..(1806)                                                  - - <400> SEQUENCE: 10                                                         - - g ttg cat aag gaa ctc ccc agt caa gat tgg - #ttt tct ttt tac gtg         gaa     49                                                                         Leu His Lys Glu Leu Pro Ser Gln Asp T - #rp Phe Ser Phe Tyr Val Glu             1              - # 5                 - # 10                 - # 15          - - gta ttc cac tgc tac act tcc gtg ata tac gc - #g gta gtt gac gga gcc            97                                                                        Val Phe His Cys Tyr Thr Ser Val Ile Tyr Al - #a Val Val Asp Gly Ala                         20     - #             25     - #             30                   - - gtt cta tac gca aac gcc gat tac aaa aca ca - #t tgt acg ata agc gat           145                                                                        Val Leu Tyr Ala Asn Ala Asp Tyr Lys Thr Hi - #s Cys Thr Ile Ser Asp                     35         - #         40         - #         45                       - - gac cga cga cat agg gaa gac gtt acg gac ga - #t tgt ctg tgt tgt cac           193                                                                        Asp Arg Arg His Arg Glu Asp Val Thr Asp As - #p Cys Leu Cys Cys His                 50             - #     55             - #     60                           - - gta tct cct caa att cgt acg ttc ggt aca ca - #g gta atg gag aac gta           241                                                                        Val Ser Pro Gln Ile Arg Thr Phe Gly Thr Gl - #n Val Met Glu Asn Val             65                 - # 70                 - # 75                 - # 80        - - gag tgt cgg gtg gta cgg gat ggt tta tgt at - #c gaa ata aaa cac gtg           289                                                                        Glu Cys Arg Val Val Arg Asp Gly Leu Cys Il - #e Glu Ile Lys His Val                             85 - #                 90 - #                 95               - - gga aaa ttc gga gca tcg tgc gta ggt gcg ta - #t aat acg cgg tat ata           337                                                                        Gly Lys Phe Gly Ala Ser Cys Val Gly Ala Ty - #r Asn Thr Arg Tyr Ile                        100      - #           105      - #           110                   - - aaa ata gcg ata ggg tcg gtg tac gat atc at - #t cta aaa cag gac ggg           385                                                                        Lys Ile Ala Ile Gly Ser Val Tyr Asp Ile Il - #e Leu Lys Gln Asp Gly                    115          - #       120          - #       125                       - - atg tcc gga aag aag cga cat agt tgc tac gt - #g tac gga atc gcc cga           433                                                                        Met Ser Gly Lys Lys Arg His Ser Cys Tyr Va - #l Tyr Gly Ile Ala Arg                130              - #   135              - #   140                           - - cgg tag gcttgcgaaa tagtgtattg ttttttatca gagttagcgt at - #acaaagga            489                                                                        Arg                                                                            145                                                                             - - tcgtcttatt ttggatcata cgttcgatga tcgttttctc cgcgtttacg tc -              #gtgaatgg    549                                                                  - - agttttgcat ggcacgcata gtatagccgt tgtaataatg gataaattgg tt -             #aggccccc    609                                                                  - - cattggggta cccgaatccc gtaatcgtta cgccctggca cacgtgtaac gc -             #ggtcacga    669                                                                  - - gcgcgaccat tcccatcgta ggaacgtgca acgttccgga cgttgtctgt at -             #acgcaacg    729                                                                  - - ccgcatcgta cgtatatttc ggatgtagga ttcgtacgaa cgccggacgc gc -             #gcgccacg    789                                                                  - - tgcgaggcgg tttcttccaa aatctagaca ggtcgacgcg tgcgttgttc gt -             #aagcatgt    849                                                                  - - tatatagcca gtataagtcg gcggacttga acggaaccat tacaaacagc gt -             #cgtattat    909                                                                  - - cgttttcttt cacggaatcc gattgggcgg attccgggta gaacatacgt at -             #cgtcgttt    969                                                                  - - ttgtcccaac gtctcgttcg aaggcacgaa cgggagcgtc gtttaaccga aa -             #caccacgt   1029                                                                  - - cgtacgagtc gatgattcgt cctaaagatc tattgtgtaa gttataacta tt -             #tcctacga   1089                                                                  - - cgatacattg tttgccgtat aagaggaaat taggaagatg tccaggaatc tt -             #ttctaaca   1149                                                                  - - gacgacgtat ctgcgcttcc tctcctttta gcccgtacgg taaacgtctt tc -             #gaacgtat   1209                                                                  - - tattgtgggt tacaaatacg tttgtgacgg atacgttgtt cgttccgtgg tt -             #taccacgg   1269                                                                  - - acattttcaa cgacattacg aacaacgcaa ctgcggtaca tgcgtacacc at -             #cgtgcatc   1329                                                                  - - gtttaaagaa atacatatcg cagaagcaag attttttttg tgttttagtc ta -             #cccaacgt   1389                                                                  - - acgcgataga acact atg agc aac tac gta aag ttc - #gac gta tcg atc         gaa    1440                                                                                       Met - #Ser Asn Tyr Val Lys Phe Asp Val Ser Ile G - #lu                         - #           150      - #           155                      - - gat gac tgt atc aat ata acg gtc agt aac ac - #t agt tta ccc atc cac          1488                                                                        Asp Asp Cys Ile Asn Ile Thr Val Ser Asn Th - #r Ser Leu Pro Ile His                160              - #   165              - #   170                           - - gta aag acc gtc ccc aaa cgc aca cat cgg ga - #c aat tac gtg ttt aaa          1536                                                                        Val Lys Thr Val Pro Lys Arg Thr His Arg As - #p Asn Tyr Val Phe Lys            175                 1 - #80                 1 - #85                 1 -       #90                                                                               - - aac act ata gac gcc tcg gac gat atc gtc tc - #t atc cta cac aac         tat     1584                                                                     Asn Thr Ile Asp Ala Ser Asp Asp Ile Val Se - #r Ile Leu His Asn Tyr                           195  - #               200  - #               205               - - ata tgg tac aga gga ttt ata ggt ctg ccg aa - #c aaa tac ggt agg gtg          1632                                                                        Ile Trp Tyr Arg Gly Phe Ile Gly Leu Pro As - #n Lys Tyr Gly Arg Val                        210      - #           215      - #           220                   - - ttc aaa gaa cta aag ctc ttc gac atc gac gc - #a aag acc aaa tac gga          1680                                                                        Phe Lys Glu Leu Lys Leu Phe Asp Ile Asp Al - #a Lys Thr Lys Tyr Gly                    225          - #       230          - #       235                       - - gat ata aat act tta ttt ttc atg tta aat tt - #a aac tcg gat cgt tgc          1728                                                                        Asp Ile Asn Thr Leu Phe Phe Met Leu Asn Le - #u Asn Ser Asp Arg Cys                240              - #   245              - #   250                           - - tgc agg aat ttt tcc aat ttc gta aca cta ca - #a aaa act ata ttc aaa          1776                                                                        Cys Arg Asn Phe Ser Asn Phe Val Thr Leu Gl - #n Lys Thr Ile Phe Lys            255                 2 - #60                 2 - #65                 2 -       #70                                                                               - - cac acg gtt acc gta tac aac tgc atc gaa  - #                  - #              1806                                                                     His Thr Val Thr Val Tyr Asn Cys Ile Glu                                                        275  - #               280                                      - -  - - <210> SEQ ID NO 11                                                   <211> LENGTH: 145                                                              <212> TYPE: PRT                                                                <213> ORGANISM: Myxoma virus                                                    - - <400> SEQUENCE: 11                                                         - - Leu His Lys Glu Leu Pro Ser Gln Asp Trp Ph - #e Ser Phe Tyr Val Glu         1               5 - #                 10 - #                 15               - - Val Phe His Cys Tyr Thr Ser Val Ile Tyr Al - #a Val Val Asp Gly Ala                    20     - #             25     - #             30                   - - Val Leu Tyr Ala Asn Ala Asp Tyr Lys Thr Hi - #s Cys Thr Ile Ser Asp                35         - #         40         - #         45                       - - Asp Arg Arg His Arg Glu Asp Val Thr Asp As - #p Cys Leu Cys Cys His            50             - #     55             - #     60                           - - Val Ser Pro Gln Ile Arg Thr Phe Gly Thr Gl - #n Val Met Glu Asn Val        65                 - # 70                 - # 75                 - # 80        - - Glu Cys Arg Val Val Arg Asp Gly Leu Cys Il - #e Glu Ile Lys His Val                        85 - #                 90 - #                 95               - - Gly Lys Phe Gly Ala Ser Cys Val Gly Ala Ty - #r Asn Thr Arg Tyr Ile                   100      - #           105      - #           110                   - - Lys Ile Ala Ile Gly Ser Val Tyr Asp Ile Il - #e Leu Lys Gln Asp Gly               115          - #       120          - #       125                       - - Met Ser Gly Lys Lys Arg His Ser Cys Tyr Va - #l Tyr Gly Ile Ala Arg           130              - #   135              - #   140                           - - Arg                                                                       145                                                                             - -  - - <210> SEQ ID NO 12                                                   <211> LENGTH: 134                                                              <212> TYPE: PRT                                                                <213> ORGANISM: Myxoma virus                                                    - - <400> SEQUENCE: 12                                                         - - Met Ser Asn Tyr Val Lys Phe Asp Val Ser Il - #e Glu Asp Asp Cys Ile         1               5 - #                 10 - #                 15               - - Asn Ile Thr Val Ser Asn Thr Ser Leu Pro Il - #e His Val Lys Thr Val                    20     - #             25     - #             30                   - - Pro Lys Arg Thr His Arg Asp Asn Tyr Val Ph - #e Lys Asn Thr Ile Asp                35         - #         40         - #         45                       - - Ala Ser Asp Asp Ile Val Ser Ile Leu His As - #n Tyr Ile Trp Tyr Arg            50             - #     55             - #     60                           - - Gly Phe Ile Gly Leu Pro Asn Lys Tyr Gly Ar - #g Val Phe Lys Glu Leu        65                 - # 70                 - # 75                 - # 80        - - Lys Leu Phe Asp Ile Asp Ala Lys Thr Lys Ty - #r Gly Asp Ile Asn Thr                        85 - #                 90 - #                 95               - - Leu Phe Phe Met Leu Asn Leu Asn Ser Asp Ar - #g Cys Cys Arg Asn Phe                   100      - #           105      - #           110                   - - Ser Asn Phe Val Thr Leu Gln Lys Thr Ile Ph - #e Lys His Thr Val Thr               115          - #       120          - #       125                       - - Val Tyr Asn Cys Ile Glu                                                       130                                                                         - -  - - <210> SEQ ID NO 13                                                   <211> LENGTH: 289                                                              <212> TYPE: PRT                                                                <213> ORGANISM: Myxoma virus                                                    - - <400> SEQUENCE: 13                                                         - - Met Tyr Phe Phe Lys Arg Cys Thr Met Val Ty - #r Ala Cys Thr Ala Val         1               5 - #                 10 - #                 15               - - Ala Leu Phe Val Met Ser Leu Lys Met Ser Va - #l Val Asn His Gly Thr                    20     - #             25     - #             30                   - - Asn Asn Val Ser Val Thr Asn Val Phe Val Th - #r His Asn Asn Thr Phe                35         - #         40         - #         45                       - - Glu Arg Arg Leu Pro Tyr Gly Leu Lys Gly Gl - #u Glu Ala Gln Ile Arg            50             - #     55             - #     60                           - - Arg Leu Glu Lys Ile Pro Gly His Leu Pro As - #n Phe Leu Leu Tyr Gly        65                 - # 70                 - # 75                 - # 80        - - Lys Gln Cys Ile Val Val Gly Asn Ser Tyr As - #n Leu His Asn Arg Ser                        85 - #                 90 - #                 95               - - Leu Gly Arg Ile Ile Asp Ser Tyr Asp Val Va - #l Phe Arg Leu Asn Asp                   100      - #           105      - #           110                   - - Ala Pro Val Arg Ala Phe Glu Arg Asp Val Gl - #y Thr Lys Thr Thr Ile               115          - #       120          - #       125                       - - Arg Met Phe Tyr Pro Glu Ser Ala Gln Ser As - #p Ser Val Lys Glu Asn           130              - #   135              - #   140                           - - Asp Asn Thr Thr Leu Phe Val Met Val Pro Ph - #e Lys Ser Ala Asp Leu       145                 1 - #50                 1 - #55                 1 -       #60                                                                               - - Tyr Trp Leu Tyr Asn Met Leu Thr Asn Asn Al - #a Arg Val Asp Leu         Ser                                                                                              165  - #               170  - #               175              - - Arg Phe Trp Lys Lys Pro Pro Arg Thr Trp Ar - #g Ala Arg Pro Ala Phe                   180      - #           185      - #           190                   - - Val Arg Ile Leu His Pro Lys Tyr Thr Tyr As - #p Ala Ala Leu Arg Ile               195          - #       200          - #       205                       - - Gln Thr Thr Ser Gly Thr Leu His Val Pro Th - #r Met Gly Met Val Ala           210              - #   215              - #   220                           - - Leu Val Thr Ala Leu His Val Cys Gln Gly Va - #l Thr Ile Thr Gly Phe       225                 2 - #30                 2 - #35                 2 -       #40                                                                               - - Gly Tyr Pro Asn Gly Gly Pro Asn Gln Phe Il - #e His Tyr Tyr Asn         Gly                                                                                              245  - #               250  - #               255              - - Tyr Thr Met Arg Ala Met Gln Asn Ser Ile Hi - #s Asp Val Asn Ala Glu                   260      - #           265      - #           270                   - - Lys Thr Ile Ile Glu Arg Met Ile Gln Asn Ly - #s Thr Ile Leu Cys Ile               275          - #       280          - #       285                       - - Arg                                                                      __________________________________________________________________________ 

What is claimed is:
 1. A method of preparation of lysates having α2,3- sialyltransferase activity including the steps of:infecting a cell culture having essentially no endogenous expression of eukaryotic α2,3-sialyltransferase with a poxviral agent having a poxviral α2,3-sialyltransferase gene, and a promoter therefor, and harvesting a lysate of said infected cell culture containing a protein having α2,3-sialyltransferase activity.
 2. The method in accordance with claim 1, wherein said poxviral alpha 2,3-sialyltransferase is a myxoma virus sialyltransferase, further comprising harvesting viral early proteins amplified in a cell line non-permissive for viral replication, and isolating said myxoma virus sialyltransferase.
 3. The method in accordance with claim 1, wherein said cultured cell line is selected from RK13 cells and CV1 cells.
 4. The method in accordance with claim 1, wherein said sialyltransferase is purified chromatographically.
 5. A compositions having in vitro α2,3-sialyltransferase activity and comprising a protein extract of a lysate of a eukaryotic cell culture having substantially no endogenous expression of eukaryotic α2,3-sialyltransferase, said lysate being produced in accordance with the method of claim
 1. 6. Poxviral α2,3-sialyltransferase produced by chromatographic purification of the composition of claim 5, said α2,3-sialyltransferase having a sialyl motif CMP-sialic acid binding site.
 7. A method for producing myxoma virus α2,3-sialyltransferase comprising harvesting viral early proteins amplified in a cell line non-permissive for viral replication, and isolating said myxoma virus sialyltransferase.
 8. An isolated DNA molecule comprising the complement of nucleotides 583-1455 of the DNA sequence of SEQ ID NO:3.
 9. An isolated DNA molecule comprising the complement of nucleotides 473-1345 of the DNA sequence of SEQ ID NO:10.
 10. A set of degenerate primers:CAP-I GGGATCCAT(A/T/C)TC(T/C)AG(A/G)CA(T/C)AA(A/G)CG (SEQ ID NO:1) CAP-II GGGATCCGC(A/G)CA(T/C)AA(A/T/C/G)CC(T/G/A)ATCAT (SEQ ID NO:2).
 11. An isolated α2,3-sialyltransferase comprising the amino acid sequence of SEQ ID NO:9.
 12. An α2,3-sialyltransferase comprising the amino acid sequence of SEQ ID NO:13.
 13. The method according to claim 1, wherein the α2,3-sialyltransferase gene is from a poxvirus from the genus Leporipoxvirus.
 14. The method according to claim 13, wherein the α2,3-sialyltransferase gene is from a myxoma virus of rabbits.
 15. The method according to claim 13, wherein the α2,3-sialyltransferase gene is from a poxvirus selected from the group consisting of myxoma virus Uriarra strain, myxoma virus Lausanne strain, Californian myxoma virus MSW San Francisco, Californian myxoma virus MSD San Diego, and SFV-OA shope fibroma virus original A strain.
 16. The α2,3 sialyltransferase according to claim 6, wherein the α2,3-sialyltransferase is from a poxvirus from the Family Leporipoxvirus.
 17. The α2,3 sialyltransferase according to claim 16, wherein the α2,3-sialyltransferase is from a myxoma virus of rabbits.
 18. The α2,3 sialyltransferase according to claim 16, wherein the α2,3-sialyltransferase is from a poxvirus selected from the group consisting of myxoma virus Uriarra strain, myxoma virus Lausanne strain, Californian myxoma virus MSW San Francisco, Californian myxoma virus MSD San Diego, SFV-OA shope fibroma virus original A strain. 